(1) Field of the Invention
This invention relates to a workpiece transferring apparatus having a clamping device which receives a workpiece from one conveyor device provided in a stage subsequent to a machining device or the like, to transfer the workpiece to another conveyor device leading to the following stage in such a manner that the workpiece may be selectively inverted in its orientation, and further having a workpiece retaining arm engaged with an inverting device. More particularly, the invention relates to a workpiece transferring apparatus wherein an endless chain engaged with a sprocket wheel which is supported in a frame and is connected to a reversible drive device to enable the chain to conduct rectilinear motion and also circular motion, in engagement with a chain guide having a circular-arc, wherein a base of a workpiece retaining arm, the arm having an outer end connected to said chain, is enabled to conduct a straight rise or a circular rotation in engagement with a slider sliding vertically along a slide guide provided at the frame, wherein a clamping device fixed monolithically to the base of said workpiece retaining arm is enabled to clamp and unclamp the workpiece, and wherein a position detection device, such as a limit switch, connected electrically to the reversible drive device is enabled to contact a dog on a workpiece retaining arm and to alter its position with respect to the frame.
(2) Description of the Prior Art
As is known well, a machining device for pressing and the like constitutes one process in a consecutive production line, and accordingly, a transfer through a plurality of stages is usually executed to optimize the process of passing the workpieces.
There are some cases where a workpiece is transferred with the same orientation from one stage of one machining process to the stage of the subsequent machining process. However, sometimes it becomes necessary to conduct the transfer with the workpiece in an inverted orientation.
When the inversion of the workpiece is conducted at an intermediate stage, for instance, a rotating device having an impeller or a rack and pinion mechanism is arranged for this purpose. For a workpiece which requires no inversion, a change of stage is sufficient for workpieces whose shape is within certain limits. However, for a workpiece whose shape has changed beyond these limits, an intermediate stage transferring device must be provided separately, and the apparatus becomes complicated by the additional provision of the sub-stage. These necessities lead to a need for numerous and cumbersome controlling measures, while the increased number of processes for changing stages brings about the disadvantages of lowered efficiency of the production line and an increase in the cost.